Portland, OR Climate & Monthly Averages
The climate of Portland
Portland has a Mediterranean climate, marked by hot, dry summers and mild, wetter winters. Average daytime highs range from about 46°F (8°C) in December to around 84°F (29°C) in August, and the city records roughly 148 days of measurable precipitation a year.
Climate quick facts
- Hottest month: August - highs near 84°F (29°C)
- Coldest month: December - highs near 46°F (8°C)
- Record high: 115°F (46°C) · Record low: 6°F (-14°C) (2015–2024)
- Wettest month: December (19 rainy days) · Sunniest: July (13.2 h sun/day)
- Climate type: Mediterranean - hot, dry summers and mild, wetter winters
- Snow: about 9 days a year
Temperatures through the year
The warmest stretch of the year centers on August. Highs average 84°F (29°C) and overnight lows stay near 59°F (15°C). The coolest month is December, with typical highs of 46°F (8°C) and lows around 36°F (2°C). Based on 2015–2024 weather data, temperatures have reached as high as 115°F (46°C) and dropped as low as 6°F (-14°C).
Rain, sun and snow
December is usually the wettest month. It brings about 8.9 inches (225 mm) of rain over 19 days, while July is the driest. July brings the most sunshine, averaging 13.2 hours of sun a day. Snow falls on about 9 days in a typical year, mostly from December through April.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 47° | 36° | 19 | 7.5 in | 4.1 h/day | 85% |
| February | 48° | 35° | 16 | 5.9 in | 5.2 h/day | 83% |
| March | 54° | 38° | 17 | 5.4 in | 7.4 h/day | 80% |
| April | 59° | 42° | 15 | 4.4 in | 8.9 h/day | 76% |
| May | 67° | 48° | 11 | 2.8 in | 10.1 h/day | 73% |
| June | 75° | 53° | 8 | 2.2 in | 12.0 h/day | 66% |
| July | 83° | 58° | 2 | 0.3 in | 13.2 h/day | 58% |
| August | 84° | 59° | 3 | 0.5 in | 12.1 h/day | 59% |
| September | 75° | 54° | 8 | 2.5 in | 9.9 h/day | 68% |
| October | 63° | 47° | 12 | 5.4 in | 7.1 h/day | 79% |
| November | 52° | 40° | 17 | 7.5 in | 5.1 h/day | 84% |
| December | 46° | 36° | 19 | 8.9 in | 3.8 h/day | 86% |
Portland month by month
Portland weather in January
January brings highs around 47°F (8°C), lows near 36°F (2°C), about 19 wet days and roughly 1 snowy days.
Portland weather in February
February brings highs around 48°F (9°C), lows near 35°F (2°C), about 16 wet days and roughly 2 snowy days.
Portland weather in March
March brings highs around 54°F (12°C), lows near 38°F (3°C), about 17 wet days and roughly 2 snowy days.
Portland weather in April
April brings highs around 59°F (15°C), lows near 42°F (5°C), about 15 wet days and roughly 1 snowy days.
Portland weather in May
May brings highs around 67°F (20°C), lows near 48°F (9°C), about 11 wet days.
Portland weather in June
June brings highs around 75°F (24°C), lows near 53°F (12°C), about 8 wet days.
Portland weather in July
July brings highs around 83°F (29°C), lows near 58°F (15°C), about 2 wet days - typically the driest month and the sunniest month of the year in Portland.
Portland weather in August
August brings highs around 84°F (29°C), lows near 59°F (15°C), about 3 wet days - typically the hottest month of the year in Portland.
Portland weather in September
September brings highs around 75°F (24°C), lows near 54°F (12°C), about 8 wet days.
Portland weather in October
October brings highs around 63°F (17°C), lows near 47°F (8°C), about 12 wet days.
Portland weather in November
November brings highs around 52°F (11°C), lows near 40°F (4°C), about 17 wet days.
Portland weather in December
December brings highs around 46°F (8°C), lows near 36°F (2°C), about 19 wet days and roughly 2 snowy days - typically the coldest month and the wettest month of the year in Portland.
Seasons in Portland
Spring (March through May)
Spring in Portland is mild, with daytime highs averaging 60°F (16°C) and nights around 43°F (6°C); expect showers on roughly 43 days across the season, plus around 3 snowy days.
Summer (June through August)
Summer in Portland is hot, with daytime highs averaging 81°F (27°C) and nights around 57°F (14°C); rain falls on about 13 days over the three months.
Fall (September through November)
Fall in Portland is crisp but comfortable, with daytime highs averaging 63°F (17°C) and nights around 47°F (8°C); expect showers on roughly 37 days across the season.
Winter (December through February)
Winter in Portland is chilly, with daytime highs averaging 47°F (8°C) and nights around 36°F (2°C); expect showers on roughly 55 days across the season, plus around 6 snowy days.
Climate questions, answered
What is the average temperature in Portland?
Is Portland hot in summer?
Is Portland cold in winter?
How many rainy days does Portland get in a year?
Best time to visit Portland
The best time to visit Portland is generally May to July and September, when warm days, manageable rainfall and plenty of daylight line up. Daytime temperatures in that window typically sit near 75°F (24°C).
Pack for Portland with a warm jacket and layers for the cooler season; a compact umbrella or rain shell - showers are a regular feature; moisture-wicking fabrics to cope with the humidity. Evenings can feel noticeably cooler than afternoons - August nights average 59°F (15°C).
Portland temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.